Called PASIPHAE (Polar-Area Stellar-Imaging in Polarization High-Accuracy Experiment), the experiment will map, with unprecedented accuracy, the polarization of millions of stars at areas of the sky away from the Galactic plane, in both the Northern and the Southern hemispheres, and use this information to locate the best regions of the sky where astronomers can look for information from the early Universe.

PASIPHAE is led by Konstantinos Tassis, Assistant Professor of Theoretical Astrophysics at the University of Crete, and it is made possible by a grant by the Stavros Niarchos Foundation. It is additionally sponsored by Infosys, India, the South African National Equipment Program, and Caltech.

PASIPHAE will use unique, innovative polarimeters that are designed specifically for this purpose and are currently under development at IUCAA; and a very large amount of observing time, generously committed by the Skinakas Observatory at its 1.3 m telescope, and the South African Astronomical Observatory at its 1.0 m telescope.

The PASIPHAE polarimetric map will be used to perform magnetic tomography of the Galaxy: it will allow to deduce the 3-dimensional structure of the magnetic field and the dust that resides in our own Galaxy. This dust acts as a “veil” preventing scientists to get vital data that will allow us to probe the first instants of the Universe, as well as the, yet-unknown, physics of Gravity at unprecedentedly high densities and temperatures.

PASIPHAE will open an invaluable and vastly under-explored window to the Universe, through the study of starlight polarization. Beyond studies of the early Universe, the survey will lead to leaps forward in some of the most actively pursued areas in Astrophysics. For Astrophysics of the highest energies, PASIPHAE will reveal the optical counterparts (which are highly polarized) for nature’s highest-energy yet-unidentified sources. At the same time, the tomographic mapping of the Galactic magnetic field that PASIPHAE will enable will allow us to back-track the paths of ultra-high—energy cosmic rays (the highest-energy particles ever observed in the Universe) to identify their sources. Finally, PASIPHAE will allow us to better understand how stars themselves – the lighthouses of the Universe – are formed out of cold interstellar gas. For interstellar Astrophysics, the role of magnetic fields as a moderator for the rate of formation of interstellar clouds and stars is currently hotly debated.

By revolutionizing the optopolarimetric capabilities of modern Astrophysics, PASIPHAE is set to catapult Greek Astrophysics into a prominent and leading position in the global scientific stage.